My child weighs perfectly fine, stop bothering me about it

I dont know if this is a uniquely Indian trait. But as a young mother, if you have any social interaction, specially with a slightly older woman out here, the first topic of conversation is that your child has lost weight or is so thin or does not look her age or some other disparging remark about the lack of physical growth of the child. I am experiencing this even more now, because as winter is making way for warmer weather, Migu is shedding layers of clothes, and possibly does look smaller than she did a month or so ago. Of course, this perfectly logical explanation which I give has no takers. 

Doctors have assured me that weight is but an incidental indicator of the child’s growth and one needs to review the development holistically in terms of milestones, rather than just as a single indicator. My logical brain accepts all of this and understands that my daughter does not lack anything.  But I guess one needs to be an Indian young mother to understand the wealth of accusations behind the tone of the older person who says your child is thin. Through those words, they seem to be summing you up, your sheer worthlessness as a mother. It is practically a judgment on your life. If you are not able to cook/coax your child to eat well, you dont have the right to call yourself a mother. 

 The long and short of this is that despite my brain firmly convinced that children know their own bodies best, I see every mealtime as an exam for myself. Meals lack the fun quotient, I am constantly anxious and no matter how much I try to make it fun for Migu, the underlying anxiety shines through. And in my desperation to make her eat something, I may frequently permit behavior, which I may have otherwise indicated to her is not acceptable. In short, I allow her to hold me to ransom, when it comes to eating something. 

So yeah, I am looking for some responses which I can use to an older aunty who ever says my child is too thin. My current stock of responses is low, in fact non-existent. Any ideas out there as to what I can actually say.